Generell informasjon Brønnbane navn Type Formål Status Faktakart i nytt vindu Hovedområde Felt Funn 30/3-7 A EXPLORATION WILDCAT P&A lenke NORTH SEA VESLEFRIKK 30/3-7 A Brønn navn 30/3-7 Seismisk lokalisering ST 8513R94-201& SP. 867 Boret i utvinningstillatelse 052 Boreoperatør Boretillatelse 903-L Boreinnretning Bore dager 95 Den norske stats oljeselskap a.s VESLEFRIKK A Borestart 13.10.1997 Boreslutt 29.01.1998 Frigitt dato 29.01.2000 Publiseringsdato 07.11.2005 Opprinnelig formål Gjenåpnet Innhold Funnbrønnbane WILDCAT NO GAS/CONDENSATE YES 1. nivå med hydrokarboner, alder MIDDLE JURASSIC 1. nivå med hydrokarboner, formasjon Avstand, boredekk - midlere havflate Vanndybde ved midlere havflate BRENT GP 56.0 175.0 Totalt målt dybde (MD) [m RKB] 6678.0 Totalt vertikalt dybde (TVD) [m RKB] 4181.0 Maks inklinasjon [ ] 73.9 Eldste penetrerte alder Eldste penetrerte formasjon Geodetisk datum NS grader ØV grader EARLY JURASSIC DRAKE FM ED50 60 46' 57.98'' N 2 53' 51.95'' E NS UTM 6738755.54 Side 1 av 5
ØV UTM 494432.48 UTM sone 31 NPDID for brønnbanen 3176 Brønnhistorie General Well 30/3-7 A was drilled on the Veslefrikk Field. The primary objective of the well was to explore the sand potential and possible hydrocarbons in the Late Jurassic sequence west of the Veslefrikk Field (the K-prospect). Well 30/7-3 S, was drilled on the same prospect in 1995, but did not reach the prospect due to an unforeseen fault system. A secondary objective was to drill through the Brent Group of the B-prospect, as a pilot well for a second sidetrack, the 30/3-7B well. Operations and results Wildcat well 30/3-7 A was drilled as a sidetrack to well 30/3-7 S, from the fixed surface installation Veslefrikk A. It was first kicked off through the 9 5/8" casing at 3459-3462 m in the primary well bore on 13 October 1997. The mill got stuck in the window and the string had to be backed off. A cement plug was set above the fish and a second window was milled from 3336 m to 3340 m. Due to possible high pressure scenarios above the strongly faulted complex penetrated by well bore 30/7-3 S it was decided to run and cement a 7" liner at 5705 m and the bottom part of the well was drilled as a 6" hole. A number of problems mainly related to kick-off, MWD, and logging at high temperatures (in excess of 150 deg C), led to 111 days spent on the well compared to the planned 33.5 days. The well was drilled to final TD at 6678 m in the Early Jurassic Drake Formation. The mud used was Ultidril, a pseudo-oil based mud system where the oil base is synthetic oil (olefines). The K-prospect was found to consist of well-cemented, fine grained and silty nonreservoir sandstones of Turonian to Coniacian age. There were no recoverable hydrocarbons in this zone. The Base Cretaceous level came in 180 m deeper than prognosed, and the Brent Group came in 168 m deeper than prognosed, whereas the Etive Formation was spot on prognosis. The Tarbert and Ness Formations were thinner, and the base Brent sand (Oseberg Informal Formation) was slightly thinner than prognosed. The logs verified hydrocarbons in the Brent group, but the reservoir quality was generally poor. The pore pressures are close to the expected values from the 30/6-11 well. The various reservoir zones did not line up along a common gradient, but seemed to be stacked, separate reservoirs. One core was cut in the Cromer Knoll Group from 5909 m to 5922 m. No fluid sample was taken. The well was plugged back to 5510 m and abandoned on 29 January 1998 as a gas/condensate discovery. Testing No drill stem test was performed. Side 2 av 5
Borekjerner i OD Kjerneprøve nummer Kjerneprøve - topp dybde Kjerneprøve - bunn Kjerneprøve dybde dybde - enhet 1 5909.0 5922.4 [m ] Total kjerneprøve lengde 13.4 Kjerneprøve tilgjengelig YES Kjernebilder 5909-5914m 5914-5919m 5919-5922m Litostratigrafi Top depth Lithostrat. unit 231 NORDLAND GP 783 UTSIRA FM 963 HORDALAND GP 2670 ROGALAND GP 2670 BALDER FM 2804 SELE FM 2844 LISTA FM 3139 SHETLAND GP 3139 JORSALFARE FM 3692 KYRRE FM 4447 TRYGGVASON FM 5852 BLODØKS FM 5864 SVARTE FM 5895 CROMER KNOLL GP 5895 RØDBY FM 5962 SOLA FM 5969 ÅSGARD FM 6024 VIKING GP Side 3 av 5
6024 DRAUPNE FM 6052 HEATHER FM 6349 BRENT GP 6349 TARBERT FM 6419 NESS FM 6504 ETIVE FM 6517 RANNOCH FM 6526 OSEBERG FM 6620 DUNLIN GP 6620 DRAKE FM Spleisede logger Dokument navn Dokument format Dokument størrelse [KB] 3176 pdf 0.41 Logger Type logg Topp dyp Bunn dyp for for logg logg BHI MPR 3336 5706 BHI MPR 5733 6678 FMT GR 6536 6592 MWD - GR RES DIR 3344 6678 RCI GR 6353 6581 RCI GR 6510 6692 TTRM GR CND ZDL MAC HDIL VSP 5681 6670 TTRM GR CND ZDL MAC MRIL 5690 6659 VSP HDIL DPIL GR 2888 3114 Foringinsrør og formasjonsstyrketester Type utforing Utforing diam. [tommer] Utforing dybde Brønnbane diam. [tommer] Brønnbane dyp Slam egenvekt ekvivalent [g/cm3] Type formasjonstest INTERM. 9 5/8 3336.0 12 1/4 3340.0 1.80 LOT LINER 7 5705.0 8 3/8 5706.0 0.00 LOT Side 4 av 5
Boreslam Dybde Egenvekt, Viskositet, Flytegrense Type slam MD slam [g/cm3] slam [mpa.s] [Pa] 2780 1.60 57.0 INTERDRILL NT 3344 1.58 36.0 ULTIDRILL 3447 1.58 36.0 ULTIDRILL 4687 1.61 28.0 ULTIDRILL 5286 1.61 36.0 ULTIDRILL 5501 1.61 34.0 ULTIDRILL 5679 1.61 30.0 ULTIDRILL 5740 1.45 29.0 ULTIDRILL 5909 1.45 33.0 ULTIDRILL 6373 1.48 36.0 ULTIDRILL 6472 1.48 36.0 ULTIDRILL 6510 1.48 33.0 ULTIDRILL 6678 1.48 DUMMY Dato, måling Side 5 av 5